Denigrins A–C: new antitubercular 3,4-diarylpyrrole alkaloids fromDendrilla nigra
摘要:
Chemical diversity is vital to antitubercular drug discovery as it ensures a novel bioactivity profile. Marine sponges have so far provided more than 1000 new bioactive molecules. Ethyl acetate extract of the marine sponge Dendrilla nigra on bioactivity-guided screening yielded three new compounds denigrins A-C, with potent antitubercular activity. Spectral and chemical analyses confirmed that these three compounds belong to the 3,4-diaryl pyrrole alkaloid category. The presence of monohydroxy substitution on benzene rings is not very common in lamellarin and related 3,4-diaryl pyrrole alkaloids isolated from marine invertebrates. Among these, denigrin C showed highest potency (minimum inhibitory concentration 4g/mL) against Mycobacterium tuberculosis H37Rv.
Total Syntheses of the Structures Assigned to Denigrins A, B, C, F, and G, 3,4-Diaryl-Pyrrole and -Pyrrolidinone Alkaloids, and the Conversion of Congener B into the Co-metabolite Spirodactylone
作者:Liangguang Yi、Shen Tan、Lorenzo V. White、Min-Yi Liang、Martin G. Banwell
DOI:10.1021/acs.jnatprod.3c01177
日期:2024.6.28
The title marine natural products have been prepared by totalsynthesis and in the case of congeners 3, 6, and 7 for the first time. Each of these was obtained by manipulation of readily prepared denigrin B (2). The structure, 3, assigned to denigrin C is shown to be incorrect. Reaction of compound 2 with DDQ has led, in high yield, to the related natural product spirodactylone (16), while treating
标题海洋天然产物是通过全合成方法制备的,同系物3、6和7是首次制备。这些都是通过操作容易制备的 denigrin B ( 2 ) 获得的。分配给 denigrin C 的结构3被证明是不正确的。化合物2与DDQ的反应以高产率产生相关的天然产物螺缩酮( 16 ),同时用PIFA/BF 3 ·Et 2 O处理相应的全甲基醚15 ,得到具有异构骨架的化合物20 。